Method and device for pressing a packing against a cylinder

ABSTRACT

A packing is pressed against a surface of a cylinder by using at least one roller which is deployed and retracted with respect to the cylinder by an adjusting mechanism. A guard is provided for covering the roller. The guard is actuated by the roller adjusting mechanism. The guard covers the roller in the direction of the cylinder and is actuated with the roller.

CROSS-REFERENCE TO RELATED APPLICATIONS

The subject U.S. patent application is the U.S. national phase ofPCT/DE01/01840, filed May 16, 2001; published as WO 01/87613 on Nov. 22,2001, and claiming priority to DE 100 24 330.4 filed May 17, 2000.

FIELD OF THE INVENTION

The present invention is directed to a method and to devices forpressing a packing, a cover or a dressing against a cylinder. A rollercan be deployed and retracted by an adjusting mechanism and can becovered by a guard.

BACKGROUND OF THE INVENTION

EP 07 12 725 B1 discloses a device that is usable for pressing againstprinting plates with the aid of a number of rollers which are disposedalong the cylinder circumference. In order to protect it from gettingdirty, the device is disposed in a box-shaped dirt guard that can bemoved out of the deployment region of the rollers. Additional openingflaps are disposed on the dirt guard and can be actuated by separateworking cylinders.

EP 04 33 798 B1 has a pivotable guard for a changing device of aprinting plate, which pivotable guard protects the entire apparatus,that is oriented toward the access side, from getting dirty. Thepressing roller is a one piece roller, and working cylinders situated atboth ends of the roller place it against the cylinder by use of a lever.

EP 07 10 556 B1 discloses a device for guiding the trailing end of aplate into a channel during plate installation. In this connection,after the leading end of the plate has been clamped in place, and aftermost of the plate has been mounted in place, a feeder carriage is movedagainst the cylinder and guides the trailing end of the plate into thechannel by the use of an insertion slider disposed on the carriage.

SUMMARY OF THE INVENTION

The object of the present invention is to produce a method and devicesfor pressing a packing, a cover or a dressing against a cylinderblanket.

The object is attained according to the present invention by the use ofat least one roller which is deployed and retracted by an adjustingmechanism. The roller can be covered, in the direction of the cylinder,by an actuating guard. Both the guard and the roller are actuated by thesame adjusting mechanism. A stop on the device that deploys and retractsthe at least one roller is engageable by the leading, acutely bent endof the packing, cover dressing or plate to be applied to the cylinder.The stop is inclined toward the cylinder. At one location, the spacingbetween the stop and the cylinder is less than the height of the acutelybent plate end.

The advantages that can be attained with the present invention arecomprised particularly in that a guard is provided for the rollers. Thisguard limits the possibility of the rollers getting dirty when they arein the retracted position. The rollers and the guard are actuated withthe same adjusting mechanism. The movements of both the guard androllers can therefore occur synchronously and without incurringadditional control and drive costs. It is particularly advantageous tocouple the movable guards to the roller supports that are moved by theadjusting mechanism.

To accomplish an exact insertion of a leading end of a packing, cover ordressing into a channel in the cylinder, at least one stop isadvantageously provided, which stop is stationary in relation to themachine frame. It is advantageous that when installing the packing,cover or dressing, the formation or structure of the stop imparts aninitial stress on the leading end of the packing, cover or dressing,which permits the leading end to engage, in detent fashion, in theprovided clamping or tensioning device in the cylinder in a manner thatis reproducible because it is guided.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the present invention are shown in the drawingsand will be described in detail below.

FIG. 1 is a cross-sectional view through a first preferred exemplaryembodiment of a device for pressing against the packing, cover ordressing in accordance with the present invention and showing the devicein the deployed position A;

FIG. 2 is a cross-sectional view through a second preferred embodimentof the present invention, and using first and second rollers forinstallation and removal of the packing, cover or dressing;

FIG. 3 is a cross-sectional view through a third preferred embodiment ofthe present invention, and using first and second rollers forinstallation and removal of the packing, cover or dressing; and

FIG. 4 is a cross-sectional view through a fourth preferred embodimentof the present invention, and with an increased stroke of the rollermovement, pivoting guards for covering the rollers, and a stop for thesecure insertion of the leading plate end.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

A cylinder 01, for example a forme cylinder or a transfer cylinder 01 ofa rotary printing press, has a packing, cover or dressing 02, forexample a printing plate 02, if cylinder 01 is a forme cylinder or arubber blanket 02, if cylinder 01 is a transfer or blanket cylinder,disposed on it during operation, as may be seen in FIG. 1. The packing,cover, dressing or blanket 02 will be referred to as a packinghereinafter.

The device for pressing the packing 02 against the cylinder 01 isadvantageously disposed so that it is stationary in relation to thecylinder 01, and only cooperates with the cylinder 01 when actuated. Inorder to install the packing 02 onto the cylinder 01 or in order toremove the packing, a device for pressing against the packing 02 similarto the one depicted in FIG. 1 can also be pivoted against the cylinder01 by the use of a device that is not described in detail here. Thiscan, for example, be achieved by the use of pivotable lever arms,through linear motion against a threaded spindle, or with other lineardrive mechanisms.

When the device for pressing against a packing 02 is in the operationalstate, as depicted in FIG. 1, i.e. when changing the packing blanket 02,the device extends with its longitudinal direction approximatelyparallel to an axis of rotation of the cylinder 01. During installationor removal of the packing 02, a number of rollers 03, which areassociated with the pressing device, are pressed against the rotatingcylinder 01 by the operation of an adjusting mechanism, generally at 04.

The packing pressing device essentially has a number of rollers 03 whichare spaced apart from one another in the longitudinal direction of thecylinder 01, roller supports 06 that support the rollers 03, theadjusting mechanism 04, a support surface 07, and possibly a frame 08.For example, the frame 08 can be disposed, in a stationary or mobilefashion, on a machine side frame that is not specifically shown. Forexample, the adjusting mechanism 04 is embodied as a reversiblydeformable hollow body 04, such as, for example a hose 04, which can beacted on with pressure fluid. The frame 08 serves to contain the rollersupports 06 and the hollow body 04 and can include the support surface07. When acted on by pressure fluid, the hollow body 04 is caused toexpand against the support surface 07 and places the roller 03 againstthe cylinder 01 by engageable with a surface 09 of the roller support 06that cooperates with the deformable hollow body 04.

In a first preferred embodiment of the device for pressing a packingagainst a cylinder in accordance with the present invention, the frame08 is disposed approximately parallel to the rotation axis of thecylinder 01 in the longitudinal direction of the cylinder 01 and isconfigured as an approximately U-shaped crossbar 08 that has a base 13and depending legs 11; 12 on opposite sides of the base 13. Between thelegs 11; 12, and oriented away from the base 13, there is a strip 14. Anumber of guides 16 extend through the strip 14, which guides 16 arespaced apart from one another in the longitudinal direction of thecylinder 01. For example, each guide 16 in the strip 14 is configured asa bore or as a bore containing a sleeve or a bearing bushing and allowsa strut, rod or tappet 17, that is associated with or a part of theroller support 06 to move in a longitudinally guided fashion.

The strip 14, together with the two depending legs 11; 12, and the base13, form a hollow chamber 18 that is extending in the longitudinaldirection of the cylinder 01. On its side oriented toward the hollowchamber 18, the base 13 of the U-shaped cross bar has the supportsurface 07 that, as discussed above, cooperates with the inflatablehollow body 04. The legs 11; 12 can also be embodied as struts or can beomitted entirely.

The inflatable or expandable hollow body 04 is disposed in thelongitudinal direction in the hollow chamber 18 between the two legs 11;12, the base 13 with the support surface 07, and the surfaces 09 of theroller supports 06 that cooperate with the hollow body 04.

The roller support 06, which is embodied with two arms, essentially hasa head 19 which is embodied, for example as a plate 19, and which plate19 is disposed in the hollow chamber 18 of the frame 08, and cooperateswith the hollow body 04. Roller support 16 also has two struts, rods, ortappets 17 that each protrude through a respective guide 16 of the strip14 and are each provided with a foot 21, which supports the roller 03.The strut 17, which may be, for example a cylindrical rod 17, isdisposed so that it can slide in respect to its longitudinal directionin the guide 16 of the strip 14. Rod 17 connects the other components ofthe roller support 06 at its respective ends, namely connecting theplate 19 disposed in the hollow chamber 18 to the foot 21, which isdisposed outside the hollow chamber 18, which foot 21 supports theroller 03, and which is embodied, for example, in the form of a leg 21.The cross section of the rod 17 approximately corresponds to the crosssection of the guide 16 and/or to the inner diameter of a bearingbushing or a sleeve provided in the guide 16 for better axial guidanceof the rod 17.

On at least one of its side surfaces 22, the leg 21 has a radial bearing23, for example a bearing bushing 23 for use in containing an axle 24that is associated with the roller 03. The roller 03 is disposed betweenthe two legs 21 so that its longitudinal axis extends approximatelyparallel to the rotation axis of the cylinder 01 during a plate change.

At each of its ends, the roller 03 has an end of the axle 24, which axle24 either passes all the way through the roller 03 or is discontinuous.These axle ends each cooperate with an associated bearing bushing 23 intheir associated leg 21. The roller 03 can be a rubber roller, a plasticroller, or a different roller 03 whose running surface is provided witha soft covering that does not damage the packing 02.

On its side oriented toward the hollow body 04, the roller support heador plate 19 has the first surface 09 that cooperates with the deformablehollow body 04. A second surface 26 of the plate 19, opposite from thefirst surface 09, cooperates as a stop 26 with the surface 27 of thestrip 14 which is oriented toward the hollow chamber 18. It isadvantageous to dispose at least one flexible element 28, such as, forexample a spring 28, between the surface 27 of the strip 14 and thesurface 26 of the roller support head or plate 19. This is achieved, forexample, by the spring 28 either encompassing the rod 17 or beinginserted into recesses in the plate 19 and the strip 14.

The roller support 06 can also be embodied as being one-armed, whereineach rod or tappet 17 is associated with an individual plate 19 that isdisposed in the hollow chamber 18. In this embodiment, two rollersupports 06, each respectively disposed in the guide 16, cooperate tosupport the roller 03. The plate 19, rod 17, and legs 21 can also beembodied of one piece with one another, wherein the roller support 06,at the end protruding into the hollow chamber 18, i.e. the head 19,advantageously has an enlarged cross section or at least a stop 26, andat least on an end protruding from the strip 14, such as the foot 21,has a bearing bushing 23.

The head 19 of the roller support 06 can also be embodied as a plate 19,which extends over several rollers 03 and on which the rods 17 and feet21 for several rollers 03 are disposed.

In each embodiment of the device for pressing a packing against acylinder, the roller supports 06 and rollers 03 are disposed on thestrip 14 so that the rollers 03 that are spaced apart from each other inthe longitudinal direction are each supported so that they can eachrotate around an axis of rotation which is extending approximatelyparallel to the rotation axis of the cylinder 01 when the device forpressing against the cylinder 01 is pivoted.

The device for pressing a packing 02 against a cylinder 01, and with anumber of first rollers 03, in accordance with the first preferredembodiment functions as follows. In order to change the printing plateor other packing 02, the pressing device is pivoted against the cylinder01 so that the rotational axis of the cylinder 01 and the axle 24 of theroller 03 extend approximately parallel to each other. In this positionof the device, the deformable hollow body 04 is acted on by pressurefluid. When the hollow body 04 is acted on by pressure fluid and theresulting reversible shape change to the hollow body 04 occurs, thedeformable hollow body 04 is supported against the support surface 07and presses all of the roller supports 06 resting against the hollowbody 04 with their support surfaces 09 simultaneously, counter to theforce of the springs 28, outward, and with the same pressure, againstthe packing 02. The rollers 03 and roller supports 06 are now disposedin the deployed position “A”, as seen in FIG. 1. A slight deviation inthe position of the device or an inclination of the cylinder 01 iscompensated for by the pressure uniformly prevailing over the entirelength of the hollow body 04 by virtue of the fact that rollers 03,which are spaced further apart from the cylinder 01, are displacedfurther out from the hollow chamber 18. All of the roller supports 06are pushed out from the hollow chamber 18 until they come into contactwith, and exert the same force against the packing 02. However, thelatter only occurs in the tolerance range established by the length ofthe rod 17 protruding into the hollow chamber 18.

In another preferred embodiment of the present invention, in addition tothe first rollers 03, which are spaced apart from one another and whichare placed against the cylinder 01 in order to install new packings 02onto it, the device can also have a number of second rollers 29, whichare placed against the packing 02 in order to remove it. This secondpreferred embodiment of the present invention is depicted in FIG. 2.

In the second embodiment of FIG. 2, with a number of first rollers 03and a number of second rollers 29, the widened U-shaped frame 08contains a widened strip 14, which has a row of second guides 31 in thelongitudinal direction of the device, with these second guides 31 beingparallel to the row of first guides 16. The second roller supports 32,with the second rollers 29, which are disposed parallel to the firstrollers 03, are supported so that they can slide in these second guides31. A second adjusting mechanism 33 such as, for example a seconddeformable hollow body 33, is disposed in the hollow chamber 18 betweenthe support surface 07 and the surfaces 34 of the second roller supports32 and is cooperating with the first deformable hollow body 04. Thefirst roller supports 06 and the second roller supports 32 can also beactuated by a single deformable hollow body 04 that would becorrespondingly embodied and positioned in a manner similar to the firstand second deformable bodies 04 and 33, respectively.

In accordance with the second preferred embodiment, in order to changethe packing 02, first the second rollers 29 are placed against thecylinder 01. This placement of rollers 29 can be executed by acting onthe deformable hollow body 33 with pressure fluid and additionally bypivoting the frame 08 if need be around a pivot axis ending in thelongitudinal direction, for example about a shared pivot axis S, so thatonly the second rollers 29 are disposed in the deployed position A andcooperate with the packing 02. After the old packing 02 is removed, anew packing 02 is then secured in place. The hollow body 04 is acted onwith pressure fluid and the frame 08 is pivoted, if need be, in theopposite direction so that only the first rollers 03 cooperate with thenew packing 02 and are disposed in the deployed position A.

If the first roller supports 06 and second roller supports 32 areactuated jointly by pressurization of a single deformable hollow body04, then the selection of the rollers 03 or 29 to be activated isexecuted exclusively by pivoting the frame 08 around the axis extendingin the longitudinal direction, for example the pivot axis S. The uniformadjusting force exerted against the cylinder 01 or against a packing 02on the cylinder 01 for a number of rollers 03 or 29 associated with onedeformable hollow body 04 is exerted by acting on the one deformablehollow body 04 with pressure fluid.

In a third preferred embodiment of the present invention, as shown inFIG. 3, for the arrangement of a number of first rollers 03 and ofsecond rollers 29, the first rollers 03 and the second rollers 29 aresituated approximately diametrically opposite from each other on theframe 08. In contrast to the device described in conjunction with FIG.1, in this third embodiment, the base 13 that borders the hollow chamber18 is eliminated. Instead of the base 13, a second strip 36 with secondroller supports 32 and the second rollers 29 is provided, which ismirror symmetrical to a plane, the plane of symmetry E1, and to thehollow body 04. The second roller supports 32 have surfaces 34 thatcooperate with the hollow body 04 and have a surface 37 that cooperatesas a stop 37 with the second strip 36. The legs 11; 12 can be elongated,thus assuring the device of being covered at the sides. The device forpressing a packing 02 against a cylinder 01, as depicted in FIG. 3 canbe pivoted by use of a device, which is not specifically shown, inrelation to the longitudinally extending pivot axis S, which lies in theplane of symmetry E1 and which extends parallel to the axles 24 of thefirst rollers 03 and to the axles 24 of the second rollers 29. With adiametrical disposition of the rollers 03; 29, the shared pivot axis Sadvantageously coincides with the line of the plane of symmetry E1 andan intersecting plane E2 extending through the axles 24 of the firstrollers 03 and the second rollers 29.

In order to change the packing 02 by use of the third preferredembodiment, initially the second rollers 29 are placed against thecylinder 01. This is accomplished by pivoting the frame 08 around thelongitudinally extending pivot axis S and then acting on the deformablehollow body 04 with a pressure fluid so that the second rollers 29cooperate with the packing 02 and are disposed in the deployed positionA. In this connection, the two roller supports 06; 32 for the rollers 03and 29, respectively are pushed apart from each other, for example untilthe stop 26 of the freely moving roller support 06 cooperates with thefirst strip 14. In a manner that corresponds to the support surface 07from the first preferred embodiment which is depicted in FIG. 1, thesurface 09 of the first roller support 06 cooperates with the hollowbody 04 as a support surface 09. When the deformable hollow body 04relaxes, the roller support 32 is reset by the spring 28. After the oldpacking 02 is removed and the new packing 02 is secured in place, theframe 08 is pivoted, for example by 180°, so that after the deformablehollow body 04 is again acted on with pressure fluid, the first rollers03 cooperate with the new blanket packing 02 and are disposed in thedeployed position A. When the hollow body 04 is again acted on, the stop37 cooperates with the second guide 36 and the surface 34 cooperates asa support surface 34 with the deformable hollow body 04.

The first roller supports 06 and the second roller supports 32 can alsobe disposed at other angles a enclosed between the first rollers 03, thehollow body 04, and the second rollers 29, as shown in FIG. 3. Thesecond and third preferred embodiments, as depicted in FIGS. 2 and 3,show the two extremes for a number of first rollers 03 and a number ofsecond rollers 29 disposed next to one another in parallel (α=0°) anddiametrically opposite one another in relation to the hollow body 04(α=180°).

The fourth preferred embodiment of the present invention, as shown inFIG. 4, shows another device for pressing against the packing 02, inwhich the stroke produced by the deformation of the deformable hollowbody 04 is multiplied into an increased movement of the rollers 03.

As seen in FIG. 4, the deformable hollow body 04 and several rollers 03are disposed, extending longitudinally approximately parallel to therotation axis of the cylinder 01, in the frame 08. The frame 08 is anapproximately U-shaped crossbar 08 with a base 13 and legs 11; 12disposed opposite each other. In an advantageous embodiment, the leglength of the leg 12 is embodied as longer than the length of the leg11. The leg 12 of the U-shaped crossbar 08 can open outward at its outerend.

The deformable hollow body 04 is disposed inside the U-shaped crossbarframe 08, extending in its longitudinal direction, between the supportsurface 07 associated with the base 13, the legs 11 and 12, and theupper surfaces 09 of the heads 19 of the roller supports 06 cooperatingwith the hollow body 04.

The roller support 06 essentially has the head 19, which cooperates withthe deformable hollow body 04, and has at least one strut rod, or tappet17 on which the roller support foot 21 is disposed and that respectivelysupports the roller 03. The strut 17 is at least disposed with its head19 positioned between the legs 11; 12 in the frame 08. It isadvantageous to provide one roller support 06 for each roller 03, andwith the roller support 06 having two struts 17, each strut beingprovided with a foot 21 for supporting the roller 03.

On its side oriented toward the hollow body 04, the head 19 of theroller support 06 has the upper surface 09, as discussed above, andapproximately perpendicular to this upper surface 09, the head 19 hastwo side surfaces 38, with which the roller support head 19 of theroller support 06 is supported against the leg 11 and/or 12 of the frame08. For example, the head 19 may be embodied as a plate 19. The sidesurface 38 can also be the surfaces oriented toward the leg 11, 12 ofseveral sliding feet 39 or supporting feet 39 that are disposed next to,and which are spaced apart from each other and are disposed on the plate19, on the sides oriented toward the legs 11; 12. The strut, rod ortappet 17 connects the plate 19, which is disposed at its first end, tothe roller support foot 21 of the roller support 06, which is disposedat its second end, and which supports the roller 03. The plate 19 andthe two struts 17 can also be embodied as being of one piece with oneanother.

In contrast to the roller support foot 21, which is rigidly connected tothe strut 17 in the first preferred embodiment, in the fourth preferredembodiment, the foot 21 of the roller support 06 is embodied as a rockeror as a one-armed lever 21, which is actuated by movement of the strut17 that functions as a tappet 17. The lever 21 is supported so that itcan rotate around a fulcrum 41 situated at a first end of the lever 21.

The fulcrum 41 of the lever 21 is disposed on a rotation axis D, whichextends approximately perpendicular to the longitudinal direction of thestrut 17 and approximately parallel to the axle 24 of the rollers 03 andwhich is stationary in relation to the frame 08. For example, thisfulcrum 41 is embodied as a linkage comprised of a fork head 42 fastenedto the frame leg 12 and a bolt 43 that passes through the fork head 42and the lever 21.

At a point that is spaced from the fulcrum 41, the strut 17 engages thelever 21. The lever 21 and strut 17 are connected to each other so thatthey can rotate around an axis which is approximately parallel to theaxle 24 of the rollers 03. This connection is made, for example, by theuse of a bolt 44, which is disposed in aligned bores in the lever 21 andin the strut 17.

The bearing bushing 23 or a similar mechanism, which is suitable forsupporting the roller 03, is disposed at the second end of the lever 21opposite from the fulcrum 41. In an advantageous configuration, twolevers 21 can be associated with a single roller support 06 torespectively support one roller 03. The roller 03 is disposed betweenthe two levers 21 so that its axle 24 extends approximately parallel tothe axis of the cylinder 01 when the levers 21 are actuated by movementof the respective strut 17 of the roller support 06.

The rollers 03 can also be placed against the cylinder 01 by use oftwo-armed levers and by differently structured or differently positionedlinkage elements, wherein when acted on with pressure fluid, thedeformable hollow body 04 actuates a drive element through itsreversible deformation, and the stroke of the resulting linear movementon the drive element is translated, possibly by a correspondingcoupling, into a movement of the rollers 03. It is advantageous toprovide a transmission or a linkage, which multiplies the stroke of thelinear movement generated in the push rod or tappet 17, duringdeformation of the hollow body 04, into a greater movement of therollers 03.

The resetting of the rollers 03 or of the roller support 06 isadvantageously produced by a spring force. For example, a spring 28acting on the lever 21 can be fastened to the frame 08 or the strut 17.It is also possible to place a compression spring between the head 19and a stop that is not shown.

In a preferred configuration of the present invention, when the deviceis not actuated, the U-shaped profile of the frame 08 is closed by theprovision of one or more guards 47 which are disposed next to oneanother in the longitudinal direction of the frame 08. Each guard 47 isfastened to the shorter leg 11 of frame 08, as seen in FIG. 4, and canpivot in relation to an axis extending in the longitudinal direction ofthe frame 08, for example by the use of a hinge 48, a strap hinge, orarticulating joints. The guard 47 is configured so that it completes theframe 08 in the circumference direction on the shorter leg 11 and at theopen end of the U-shaped cross section. When the lengths of legs 11 and12 are the same, the guard 47 only closes off the open end of theU-shaped frame 08.

On the side oriented toward the inside of the frame 08, the guard 47has, for example, a coupler 49, which is disposed, at a first end, onthe guard 47 and at a second end, on the roller support 06, andpreferably on the strut 17, so that coupler 49 can pivot around an axisapproximately parallel to the longitudinal direction of the frame 08.The pivoting connection of the coupler 49 to the guard 47 is embodied,for example, as a hinge joint with a link plate 51 and a bolt 52, all asseen in FIG. 4. The coupler 49 is fastened to the strut 17 for exampleby the use of a bolt 53, which is received, in a form-fitting manner, ina bore 54 in the strut 17. The guard 47 and the coupler 49 are disposedon the frame 08 or on the strut 17 so that when the roller support 06 isin the rest position, i.e. when the strut 17 is not slid toward theopening in the frame 08 by the pressurization of the deformable hollowbody 04, the guard 47 and the U-shaped frame 08 together encompass therollers 03 and the adjusting mechanism. In other words they completelyenclose the roller support 06 and the hollow body 04.

The guard 47 can also be coupled to the roller support 06 by otherlinkage arrangements so that it is opened or closed simultaneouslyduring deployment or retraction of the rollers 03 without incurringadditional drive or control costs. It is also possible to provide aparallel arrangement of a number of deformable hollow bodies 04 next toeach other in the longitudinal direction of the cylinder 01 or one afteror beside the other, in the circumference direction of the cylinder 01,for example in order to actuate first or second rollers 03; 29 in amanner that corresponds to the apparatus according to the secondpreferred embodiment, as shown in FIG. 2. The first and second rollers03; 29 can also be disposed next to one another, for example inalternating fashion, in the longitudinal direction of the cylinder 01,wherein the first rollers 03 cooperate, by the provision of a firstroller support 06, with a first deformable hollow body 04 and the secondrollers 29 cooperate by the provision of a second roller support 32,with a second deformable hollow body 33.

The pivoting frame 08 described in the fourth preferred embodiment, asshown in FIG. 4, is preferably disposed so that it is stationary inrelation to the cylinder 01, and is parallel to the cylinder'srotational axis. The frame 08 and the guard 47 can be embodied so thatwhen the guard 47 is in the closed position, there is an extremely shortdistance d47, of preferably between 20 and 25 mm, in an engagementregion between the guard 47 and the cylinder 01. When the device isdisposed between two cylinders 01 that touch, for example between aplate cylinder and a rubber blanket cylinder of a printing press, theform of the frame 08 and the guard 47 can be embodied so that the devicealso functions simultaneously as a guard that prevents objects frombeing pulled in between the two rotating cylinders 01. To this end, amaximal distance of d12=6 mm and/or d47=6 mm should be maintained in therespective outer engagement region between the cylinder 01 and the frame08 and/or the guard 47, for example between the free end of the leg 12and the cylinder 01 or, when the guard 47 is open, between the free endof the guard 47 and the cylinder 01. It is advantageous to maintain anobtuse angle toward the operational side in the above-mentionedengagement regions between the cylinder 01 and the pressing device. Thiscan occur by correspondingly configuring the frame 08 and guard 47 or byalso providing sheet metal strips, for example.

In a preferred embodiment of the present invention, as is also shown inFIG. 4, a stop 56 is disposed at the end of the leg 12 and is orientedtoward the cylinder 01 in order to facilitate an even, guided placementof the printing plate 02 to be installed on the cylinder 01. The stop 56can be of one piece construction. Preferably, several stops 56 areprovided on the frame 08, which several stops 56 are disposed next toeach other and which are spaced apart from one another in thelongitudinal direction of the frame 08. They are attached to the frame08 by use of positive and/or frictional engagement devices, for exampleby the use of screws 57 at a curved lower end of the leg 12. However,the stops 56 can also be part of the leg 12. If the stops 56 areattached to the leg 12 by screws 57, it is advantageous for the stops 56to be adjustable in relation to the position of the cylinder 01, forexample by embodying bores 58 in the leg 12 and through which the screwspass as oblong holes.

On a side 59 of stop 56, which side 59 is oriented toward the cylinder01 and which cooperates with a leading end 62 of the printing plate 02,the form and position of the stop 56 are embodied in such a way that adistance d56 between the side 59 of the stop 56 and the surface of thecylinder 01 tapers in the circumference direction of the cylinder 01.For example, the side 59 can be embodied of two pieces and so that it isangled in relation to a line 61 extending parallel to the rotation axisof the cylinder 01, wherein the first section of the side 59 disposed inthe insertion region of the leading end 62 of the printing plate 02 isinclined less sharply in relation to the cylinder 01 and the subsequentsecond section is inclined more sharply in relation to the cylinder 01.The distance d56 between the cylinder 01 and the stop 56 should, on theline 61 of the bend 61 or at least in the course of the second sectionof the side 59, be less than the height d62 of the bent leading end 62of the printing plate 02.

In accordance with the fourth exemplary embodiment of the device forpressing a packing against a cylinder, in accordance with the presentinvention, the installation of the packing 02 on the cylinder 01 by useof the device of the present invention takes place as follows: The formecylinder 01 is initially rotated into a position in which a cylindergroove or channel opening 63 that will receive the bent leading end 62of the packing, such as a printing plate 02, comes to rest approximatelyopposite from the stops 56. With its bent leading end 62, the printingplate 02 is inserted between the forme cylinder 01 and the pressingdevice and is positioned against the stops 56. When the printing plate02 is inserted or pushed further toward the stops 56, the bent leadingend 62 of the printing plate 02 is prestressed by the form of the stops56 and automatically snaps into the cylinder channel opening 63. Afterthe leading end 62 of the printing plate 02 has been clamped in thechannel, the deformable hollow body 04 is acted on with pressure fluid.This opens the guard 47 in response to the movement of the strut 17 andsimultaneously places several individually movable rollers 03 againstthe cylinder 01. If space conditions require, after the leading end 62of the printing plate 02 is clamped in position and before the openingof the guard 47 and the deployment of the rollers 03, the cylinder 01can first be repositioned, either in the production direction or in theopposite direction. The repositioning of the cylinder 01 occurs, in anadvantageous fashion, so that the rollers 03 are placed against thepacking, such as a printing plate 02 either directly on, or close to thechannel opening 63 in the cylinder 01. After the rollers 03 aredeployed, the cylinder 01 is rotated in the production direction untilthe rollers 03 again come to rest against the channel 63 and now willguide a trailing plate end into the channel opening 63.

The opening and closing of the locking mechanisms for the leading end 62of the printing plate or packing 02 and the trailing end of the plate orpacking 02 in the channel opening 63 are preferably actuatedautomatically and are coordinated with the sequence of theabove-described procedures of the plate replacement. The removal of thepacking 02 from the cylinder 01 essentially occurs in a reversesequence.

All of the preferred embodiments of the present invention, as set forthabove, have the common feature that a single adjusting mechanism 04 or33 is used to respectively place a number of first rollers 03 and/or anumber of second rollers 29, which are actuated simultaneously anddirectly, against the cylinder 01. This is because the adjustingmechanism, in the form of a deformable hollow body 04, cooperates withthe surface 09; 34 of a roller support 06; 32. In all of the preferredembodiments, in the deployed position A, the same force is exerteddirectly on all of the rollers 03; 29 over the length of the device.

While preferred embodiments of a method and devices for pressing apacking against a cylinder, in accordance with the present invention,have been set forth fully and completely hereinabove, it will beapparent to one of skill in the art that a number of changes in, forexample the overall size of the cylinder, the type of rotary printingpress used, and the like could be made without departing from the truespirit and scope of the present invention which is accordingly to belimited only by the appended claims.

What is claimed is:
 1. A method for pressing a packing against acylinder including: providing at least one roller; providing anadjusting mechanism for deploying and retracting said roller; providingan actuatable guard for covering said roller in a direction of thecylinder; and actuating said guard and said at least one roller usingsaid adjusting mechanism.
 2. A device adapted to press a packing againsta cylinder comprising: at least one roller supported for deployment andretraction with respect to the cylinder; an adjusting mechanism useableto accomplish said deployment and said retraction of said at least oneroller; and an actuatable guard useable to cover said roller in adirection of the cylinder, said actuatable guard being actuated withsaid roller by said adjusting mechanism.
 3. The device of claim 2further including a stationary pivot axis, said guard being disposed forpivotal movement about said stationary pivot axis.
 4. The device ofclaim 3 wherein said at least one roller has a roller axle of rotationand further wherein said stationary pivot axis is generally parallel tosaid roller axle of rotation.
 5. The device of claim 2 wherein saidguard is actuatable directly by said adjusting mechanism.
 6. The deviceof claim 2 further including a linkage system between said guard andsaid adjusting mechanism.
 7. The device of claim 2 further including aroller support, said roller support supporting a plurality of saidrollers, said guard being coupled to said roller support.
 8. The deviceof claim 7 further including a coupler, said coupler extending betweensaid guard and said roller support and being connected in a pivotablemanner to both guard and said roller support.
 9. The device of claim 2wherein said adjusting mechanism is a reversibly deformable hollow body,said hollow body being adapted to be acted on by a fluid under pressure.